Problems with ruined heat brick thread
Hello
I write this post because we've had some problems with our printer. We should probably have consulted this forum earlier
The printer was working without any problems after assembly and calibration.
The problem started with filament curling up the hotend, ruining prints. This happened after we had been trying out ABS and going back to PLA again.
We noticed a lot of tar like plastic residue on the nozzle. We screwed the nozzle out and cleaned it mechanically, carefully with a scalpel.
After we put it back on (the nozzle was tightened as much as possible while hot), the plastic was no longer curling up, great! But now plastic was oozing out in wrong places, from the hole in the heater block it seemed! The blob was getting bigger and would ruin prints.
Not knowing what else to do, we took the hotend apart to find the problem. It was almost impossible to screw the nozzle body out of the heat block! We had to use some big pliers to grab the nozzle body.
The heat block was gunked with plastic which we removed by heating the block and wiping it off.
Now we want to assemble the hotend again, but it is impossible to put the nozzle body into the heat block again. We have followed this guide partially http://manual.prusa3d.com/Guide/How+to+replace+PTFE+tube/82 because it shows how to assemble and disassemble the hotend. We just left the tube in.
We think that something must have been wrong with the way the nozzle body was screwed into the heat block when we recieved it - thus ruining the thread making it so hard to take apart and impossible to put together again.
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Did we do something wrong in this process?
Are we correct to assume that the filament coming out of wrong places was because of the nozzle not being tightened enough because plastic was stuck in there?
We have sourced a new E3D lite hotend from a local supplier and the printer is working great now. We just want to make sure we understand what went wrong, such that we can avoid the same problems in the future.
Thanks in advance
Re: Problems with ruined heat brick thread
Hi you should always unscrew the hot end whilst it is hot.
I then use Coppa Slip lubricant wneh re inserting the tip...
if re assembling from total dissassembly, screw the tip all the way in first, and back it off about 1/4 turn, then tighten the heat break tube against it, finally nip the tip tight against the heat break tube to prevent leakage.
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
Re: Problems with ruined heat brick thread
So if we use some sort of lubricant we should be able to screw the nozzle body into the heat brick again?
Re: Problems with ruined heat brick thread
Hi Theis,
Having switched from ABS back to PLA, it's possible some ABS remained in the thread. I believe that when you reassembled the extruder, the body was not properly reinserted, letting material leaking between the heat block and the heat body.
You should first remove material from the internal thread.
Try to heat it, using protecting glove, first gently use a screwdriver to remove most of the material. Do not force to avoid damaging the thread.
Then use a bolt with the same diameter, and gently screw the bolt in and out to remove melted material. Better use a pump plier instead of the plier provided with the printer. Try with a low temperature first (ie 180 °C) and increase the temperature if needed. Do not force the bolt and do not increase the temperature too much to avoid burning material.
I'm like Jon Snow, I know nothing.